Polishing disk



G. P. DESPRET POLISHING DISK Dec. 10,v 1929.

'Filed July 26. 1927 .Huur/wy.

Patented Dec. 10, 1929 UNITED STATES PATENT OFFICE GEORGES PAUL DESPRET, OF PARIS, FRANCE, ASSIGNOR T0 COMPAGNIES RUNIES DES GLACES & VERRES SPECIAUX DU NORD DE LA FRANCE, OF BOUSSOIS S/SAWIBRE.

FRANCE POLISHIN Gr DISK Application filed July 26, 1927, Serial No. 208,565, and in France .Tuly 12, 1927.

The present invention relates to improvements in disks used for polishing glass plates. The characteristic features of the invention will be clearly set forth in the following description which refers to the appended drawing in which:

Fig. l shows the construction of the polishing disk presently in use in glassworks and Fig. 2 shows the improved polishing disk according to this invention.

As shown in Fig. 1 in the usual construction of the polishing disks to which a rotary motion in a horizontal plane is imparted, the felt sheet F, which receives the emery dust and is adapted to rub upon the glass plate, is pressed by means of a hydraulic press upon the cast iron body P of the disk, and is maintained thereon by a thin outer iron hoop C.

rThis construct-ion offers the following drawback: The felt disk consisting of hair, mixed or not with wool, its strength is due to the mingling of the hair produced byY a suitable foltering motion followed by a fulling motion; when the felt is pressed upon the body of the polishing disk the outer libres are drawn in the part A, so that the mingling of the hair is in part destroyed and a region of smaller strength is created at A. This is evidenced by the fact that in such construe-- tion, the felt. disk becomes rapidly split at A and is then out of use.

It is however difficult to substitute any other means for securing the felt sheet upon the polishing disk. As a matter of fact the polishing work requires that the felt sheet be freely secured upon the cast iron body of the polishing disk, so that, after each polishing operation, the felt sheet, which is choked by the emery dust, may be cleansed by water circulating between the felt sheet and the cast iron body, so as to remove the emery dust. For this reason, other means, such as gluing, previously employed for securing the felt sheet, and with which the life of the felt sheet was preserved, were not satisfactory as regard the quality of the polishing work performed therewith.

According to the present invention the pressing operation is dispensed with and the felt sheet is however freely secured upon the polishing disk.

rPhe edges of the polishing disk P 2) are therefore turned up so as to assume an oblique position and to allow of securing the felt sheet by means of bolts B, the heads whereof are sufficiently distant from the surface of friction so as to prevent their Contact with the glass plate, even when the felt sheet 1s worn out.

The felt sheet is merely placed upon the polishing disk, without any pressing, i. e. without having any of its parts drawn and weakened, and it can be readily cleansed and the emery removed therefrom. It is even feasible to remove the felt sheet by unscrewing the bolts B, in view of a thorough cleansing.

rIfhe life of the felt sheet is thereby doubled, while a very satisfactory polishing may however be obtained.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

Polishing disk comprising a metal body having its edges turned up obliquely alongv its whole periphery, a felt sheet merely applied upon said body and bolts for securingl the edges of said feltsheet to said edges of the body along the whole periphery of this latter.

In testimony whereof I have signed my name to this specification.

GEORGES PAUL DESPRET. 

